I have a sensor with (Infrared LED) with a serial connection connected to Raspberry Pi 4B. The serial sensor has built in USB converter. The USB part of dmesg is:
[ 10.815246] usbcore: registered new interface driver usbserial_generic
[ 10.815292] usbserial: USB Serial support registered for generic
[ 10.836293] brcmfmac: brcmf_fw_alloc_request: using brcm/brcmfmac43455-sdio for chip BCM4345/6
[ 10.836803] usbcore: registered new interface driver brcmfmac
[ 10.841453] brcmfmac mmc1:0001:1: Direct firmware load for brcm/brcmfmac43455-sdio.raspberrypi,4-model-b.bin failed with error -2
[ 10.858600] uart-pl011 fe201000.serial: no DMA platform data
[ 10.993336] usbcore: registered new interface driver cp210x
[ 10.993383] usbserial: USB Serial support registered for cp210x
[ 10.993447] cp210x 1-1.3.3:1.0: cp210x converter detected
[ 10.998418] usb 1-1.3.3: cp210x converter now attached to ttyUSB0
The connection is running several days, but then the connection is interrupted. On dmesg the following error is shown:
[171331.973479] usb 1-1.3: clear tt 1 (9031) error -71
Recovery is can only be done by rebooting the raspberry. Stopping and starting the program does not help.
OS is OpenSUSE Tumbleweed.
Thanks for any answer, Johannes